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authorJens Axboe <jens.axboe@oracle.com>2008-01-29 14:51:59 +0100
committerJens Axboe <jens.axboe@oracle.com>2008-01-29 21:55:07 +0100
commit8324aa91d1e11a1fc25f209687a0b2e6c2ed47d0 (patch)
treec63753df94b741d328840edabde74462591ca0b3 /block/blk.h
parenta168ee84c90b39ece357da127ab388f2f64db19c (diff)
downloadlwn-8324aa91d1e11a1fc25f209687a0b2e6c2ed47d0.tar.gz
lwn-8324aa91d1e11a1fc25f209687a0b2e6c2ed47d0.zip
block: split tag and sysfs handling from blk-core.c
Seperates the tag and sysfs handling from ll_rw_blk. Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
Diffstat (limited to 'block/blk.h')
-rw-r--r--block/blk.h29
1 files changed, 29 insertions, 0 deletions
diff --git a/block/blk.h b/block/blk.h
new file mode 100644
index 000000000000..d88549df1b09
--- /dev/null
+++ b/block/blk.h
@@ -0,0 +1,29 @@
+#ifndef BLK_INTERNAL_H
+#define BLK_INTERNAL_H
+
+extern struct kmem_cache *blk_requestq_cachep;
+extern struct kobj_type blk_queue_ktype;
+
+void __blk_queue_free_tags(struct request_queue *q);
+
+void blk_queue_congestion_threshold(struct request_queue *q);
+
+/*
+ * Return the threshold (number of used requests) at which the queue is
+ * considered to be congested. It include a little hysteresis to keep the
+ * context switch rate down.
+ */
+static inline int queue_congestion_on_threshold(struct request_queue *q)
+{
+ return q->nr_congestion_on;
+}
+
+/*
+ * The threshold at which a queue is considered to be uncongested
+ */
+static inline int queue_congestion_off_threshold(struct request_queue *q)
+{
+ return q->nr_congestion_off;
+}
+
+#endif